IO or OB?

[mtrainTurbo]

Re: IO or OB?

Nope, i disagree with your disagreement!

Given identical hulls and identical horsepower, the OB is going to have far superior shallow water capability no matter what. Two reasons

1) Outboards are lighter. A 200 hp outboard is 4-500 pounds. A similar v6 or small v8 setup is going to be 1000+ pounds. 500 pounds at the very stern of a boat is going to affect draft. This by itself means that if everything else is identical, the outboard still wins for shallow water capability.

You're making an assumption that we're talking 2 strokes. Most newer 4 stroke outboards have closed the gap in weight, and if we're talking twin outboards to a single big block stern drive....

2) tilt. Lets see you tilt an I/O up to the point the prop is just at the surface, and then come back and say how long your U joints last. OB's also have a mechanical advantage when tilted because of the higher pivot point, they get more of the lower unit out of the water and increase your shallow water capability.

If its that shallow, you still aren't going anywhere with control because the prop isn't producing adequate thrust, and if you need to tilt the drive/engine up so that the blades are piercing the water, you may as well get out and push - you're on the bottom anyway.

But for the record, stern drives at idle speeds with reasonable tilt do not eat U Joints. My home waters are the Fox River Chain O Lakes, so I am well versed in shallow water sterndrive operation. Heck, I managed for 3 years with a Volvo Penta AQ that didn't even have power trim.

3) (ok, i said i had 2, but this one needs to go in here also!) Jack plates... They don't work so well on I/O's, but they allow an outboard to go to the absolute minimum water depth. At slow speed you might be able to have the entire lower unit (or at least the prop) above the bottom of the hull.

Again, location. Jack plates are not in common use on boats around here.

I would advise a lot of you to keep in mind his home waters. He should go down to his waterway and see what the majority of boats are using.

When you factor in his suggested price range (which is to say, pretty much nothing) he's shopping based on ONE factor, and only one factor: Condition for the price, and damn whatever is on the back of it. That means if he finds the worlds cleanest boat, but it has a Force OB on it, thats what he gets.

 

[ezmobee]

Re: IO or OB?

Forgive us for assuming you would actually maintain the boat properly. The bellows are a scheduled maintenance item, like an oil change on a car. The risers rust out in (see a pattern developing here?) salt water, and especially if you run a boat with raw water cooling.

Doesn't change the fact that outboards do not have this maintenance item to maintain.

 

[edwardh1]

Re: IO or OB?

in coastal south carolina (salt water and beaches) its 10/1 or 15/1 outboards to sterndrives.

 

[geeco1]

Re: IO or OB?

When I was looking, it came down to one simple deciding point.... weight. Since I am towing with a minivan, I wanted to make sure that I reduced the tow weight as much as I could without sacrificing boat size. That is the main reason that I went with an aluminum boat with an OB.

 

[Kracken]

Re: IO or OB?

24 posts and nobody has said it yet?

REALLY?


OK then.....

Chicks dig I/Os


argument over.

 

[Home Cookin']

Re: IO or OB?

same here, on boats under 25', and there are a lot of big boats with OB's on them.

Could have something to do with the large number of boats left in the water. A trailer community is a whole 'nother thing.

One aspect of the discussion to consider--not all owners do some or all of their own maintenance and repairs, so the comparisons of what's "easy" might not pertain. Although I don't know much about inboards, I knwo a lot of OB's that last a long long time in salt water with very little maintenance. Not recommending it, just saying.

 

[H20Rat]

Re: IO or OB?

You're making an assumption that we're talking 2 strokes. Most newer 4 stroke outboards have closed the gap in weight, and if we're talking twin outboards to a single big block stern drive....

Pretty sure the OP isn't looking at a new 4 stroke or twin outboards... Someone with a 25 year old 18' bowrider usually isn't going to jump right into one of those, especially since he doesn't want to shell out $1800 for a new inboard.

If its that shallow, you still aren't going anywhere with control because the prop isn't producing adequate thrust, and if you need to tilt the drive/engine up so that the blades are piercing the water, you may as well get out and push - you're on the bottom anyway.

Depends on how you boat. In some areas people will go a LONG ways in water that is 2 feet deep or less just to get to their favorite fishing hole. Pushing isn't an option.

But for the record, stern drives at idle speeds with reasonable tilt do not eat U Joints. My home waters are the Fox River Chain O Lakes, so I am well versed in shallow water sterndrive operation. Heck, I managed for 3 years with a Volvo Penta AQ that didn't even have power trim.

The Mercruiser manual warns that damage will occur if operated above the trim range at rpm's above 1200. I suspect this is even pushing the max U-joint angle quite a bit. (All u-joints have rated operating angles given a specific RPM, 15 degrees is common. A tilted lower unit is far above that) I've personally seen a number of destroyed U joints from inexperienced boaters with too much hand on the throttle when the drive was up.

Again, location. Jack plates are not in common use on boats around here.

I would advise a lot of you to keep in mind his home waters. He should go down to his waterway and see what the majority of boats are using.

He must have made reference to his location in another thread? none in this one... Jack plates have a specific purpose on a specific type of boat. They are an OPTION that an I/o will never have that allows minimal draft...


anyway, all things considered, when you take into account what the OP is looking for, a older (2 stroke) boat in an identical hull will still always have less draft on plane and off than an I/O.

 

[rbh]

Re: IO or OB?

I do not think there is going to be a winner for this discussion.

 

[Philster]

Re: IO or OB?

Well, 4-stroke big-power outboards are cropping up everywhere. They are getting more complicated and more stressed. Used to be that outboards were 2-strokers up and down the coast and all over, and were much, much simpler/bullet-proof. Further, 2-strokers naturally make more power more easily (light up faster and rev higher). When the world moved to 4-strokers for efficiency and emissions benefits, the power had to be coaxed from them.

Well well... now that the pressure is on the 4-stroker outboards, they have to step up and deliver fast hole shots, peak RPM and advertise the power, so they've grown in weight/size/complexity and -- cha-ching -- they ain't cheap!

Now the playing field of I/O vs O/B is getting somewhat more level. It's now becoming a comparison of one high-performance 4-stroke motor (o/b) vs. another high-performance 4-stroke motor (i/o) and they just happen to sit in different positions on the boat, with one offering some advantages (maybe the o/b).

I saw a 350 HP Yammy on a fishing boat. That is a sophisticated, modern engine under great stress, with camshafts and all the electronic goodies and need for precision spark and fuel delivery that is much more like the car engines that have been going into I/O's for decades.

I/O's have been less reliable in my experience because they are being compared to all the 2-stroke O/B's on so many boats. Now that big, stressed, precision O/B monsters are here, it's gonna be hard to spot a difference.

 

[SeanT]

Re: IO or OB?

24 posts and nobody has said it yet?

REALLY?


OK then.....

Chicks dig I/Os


argument over.

Quoted for truth. Chicks like to tan on the sun decks!

Some opinion from someone who is technical and can do some of my own repairs, but I'm not a super-knowledgeable engine guy:

When I was looking for my first boat, I wanted an outboard because that's what I remembered as a kid and it felt less complicated to me. I nearly bought a 16' Larson with a 140HP Evinrude. But then I saw this very pretty 1988 VIP that literally sparkled (flake paint). I fell in love and bought it, along with a 4.3L OMC (Chev) engine + outdrive. Though we had a bit of fun with it, it spent most of the time in the shop. Partly because it was an OMC (hard to get parts), partly because my service people (at the time) were idiots, and partly because I hit a rock in the middle of the lake when I came off plane and bent the prop shaft (freak accident, wrong place wrong time, no buoys).

None of the above is really IO vs OB territory, I admit I didn't make a smart IO purchase, as nice as the boat was otherwise. In that particular case, I really wish I had went with the OB, but hind sight is 20/20, and as expensive as it was, I learned a lot (I read the engine manual for my IO...)

So, now I have a direct drive IB (neither IO nor OB) and I couldn't be happier. The engine is way easier to work on than my IO, it's simpler like the OB (i.e. theres no leg, bellows, gimbal, etc), and I love love love my boat.

No matter what you decide, just make sure you learn from it, both good and bad. Boating is a lifestyle, I think it's more than a hobby if you want to do it right.

Good luck!

 

[mtrainTurbo]

Re: IO or OB?

Depends on how you boat. In some areas people will go a LONG ways in water that is 2 feet deep or less just to get to their favorite fishing hole. Pushing isn't an option.

And some people don't fish. Here again, you're giving advice based on an assumption - we don't know how he wants to boat.

I am not picking on you, just playing Devil's Advocate. I grew up in the 1000 Islands of upstate NY, and up there, a bottom strike meant running into a submerged wall of granite. You NEVER went anywhere unless you had charts, and NEVER went anywhere that had less than 10 feet of water unless you knew EXACTLY what you were doing.

When I moved to Chicago and saw people putting their boat's on plane in 2 feet of water, I nearly had a heart attack.

The Mercruiser manual warns that damage will occur if operated above the trim range at rpm's above 1200. I suspect this is even pushing the max U-joint angle quite a bit. (All u-joints have rated operating angles given a specific RPM, 15 degrees is common. A tilted lower unit is far above that) I've personally seen a number of destroyed U joints from inexperienced boaters with too much hand on the throttle when the drive was up.

If you're at anything above idle speed with the outdrive tilted up, then yeah, you're going to cook the U Joints. Idle speed on most modern sterndrives is around 800 RPM. If you are in trailer/tilted up range, you are to be at DEAD IDLE, nothing more. And frankly, I doubt you will want to be going faster than that in an outboard anyway - it would put serious strain on the transom.

He must have made reference to his location in another thread? none in this one... Jack plates have a specific purpose on a specific type of boat. They are an OPTION that an I/o will never have that allows minimal draft...

No, he didn't. Which is why I am worked up over some of these responses - he is getting advice from die-hard salt water boaters. Most of this advice would be completely un-usable for my home waters, and borderline complete BS. My opinions would be different if all my boating consisted of open ocean fishing. It isn't. Most of my boating is Lake Michigan and protected lakes and rivers, cooking a steak off the back of my boat on my Magma grill while tucked in a nice cove.

anyway, all things considered, when you take into account what the OP is looking for, a older (2 stroke) boat in an identical hull will still always have less draft on plane and off than an I/O.

I suppose I would agree with that, all being equal. However, given the nature of the question, there's far too many variables to make a judgement. And thats not a statement against you, its more a call for more information from the OP. Where does he boat, what kind of boating does he do, what is his budget, what is his tolerance for repairs, and what is the used boat inventory like around his area?

 

[25thmustang]

Re: IO or OB?

We have 3 boats right now.

18' Bowrider with an O/B.

27' Express with twin I/O.

29' Express with twin I/B.

All have strengths and weaknesses. I preferred the I/B, due to the fact I like the simplicity of it. I would choose the motor that best suited the boat I wanted, that best suited the boating I wanted to do.

 

[2ndtry]

Re: IO or OB?

And some people don't fish. Here again, you're giving advice based on an assumption - we don't know how he wants to boat.

Dude, this started when you said OB's aren't better in shallow water, which is false. He isn't assuming anything, just saying if boating in shallow water IS a an issue, he should consider an OB.

 

[45Auto]

Re: IO or OB?

and the bellows can break sinking your boat, or the riser (s) rust out

Don't forget how easily many outboards can sink from taking waves over the stern through the motor cutout.

Seaworthy, the damage avoidance newsletter from BoatU.S. Marine Insurance, took a close look at the claims files and identified the myriad reasons why outboard powered vessels sink.

When underway, outboard powered boat owners should be concerned about swamping from the transom. Transom wells are sometimes poorly designed and every effort should be made to prevent water, even from the boat's own wake, from entering the cockpit or bilge area."

The results are as follows:

Sinking At The Dock

Rain/snow 47%
Underwater Fittings 20%
Above the Waterline Fittings 10%
Poor Docking Arrangements 9%
Water Over Gunwales/Transom 9%
Other 5%

Sinking While Underway

Water Over Gunwales/Transom 32%
Livewell/Baitwell Plumbing 20%
Drain Plug 16%
Struck a Submerged Object 12%
Other 12%
Construction 8%

http://www.sportfishingmag.com/article.jsp?ID=43587&destinationID=

They also did a study on I/O sinkings:

http://www.marlinmag.com/news/news/...hy-inboardoutboard-powerboats-sink-48634.html

Any boat can sink - don't maintain it or pay attention to conditions, don't be surprised when it sinks.

 

[45Auto]

Re: IO or OB?

Where does he boat, what kind of boating does he do, what is his budget, what is his tolerance for repairs, and what is the used boat inventory like around his area?

MTrain, you are obviously a newbie here on Iboats. Logic and reason have no place in these discussions!

This is just a repeat of the I/O vs OB threads that show up here every couple of months. I personally just copy and paste my responses from the old ones to keep things interesting. Next step is usually somebody posting about how all outboards don't have transom cutouts so the waves over the stern don't apply to them.

 

[SeanT]

Re: IO or OB?

 

[dirtdiver]

Re: IO or OB?

Kinda off topic, but if the boat is new to you aside from water coming in. How do you know when to replace the bellows?

 

[45Auto]

Re: IO or OB?

First thing I do on an I/O when I get it is to replace all the bellows unless the original owner has a receipt showing they've been replaced within the last couple of years. Costs about $100. Then I replace them every 5 years if I keep the boat that long.

 

[apache61]

Re: IO or OB?

Have been in boats with I/O and lost the starter got towed back to dock. Been in boats with O/B lost started and pull started a 150 hp evinrude 2 pulls and we were on our way. Also had a dimwit step on the fuel line and bust the fitting at the transom box O/B got it fixed but never had it happen on a I/O. I am an O/B person but I also like I/O and damn near all boats.

 

[seaboo]

Re: IO or OB?

Have been in boats with I/O and lost the starter got towed back to dock. Been in boats with O/B lost started and pull started a 150 hp evinrude 2 pulls and we were on our way. Also had a dimwit step on the fuel line and bust the fitting at the transom box O/B got it fixed but never had it happen on a I/O. I am an O/B person but I also like I/O and damn near all boats.

But in a pinch (with an I/O) you could go to auto zone, pick up a starter and be back on the lake with 15 minutes of wrenching (depending on access of course).

Personally I like I/O's (large sundeck, I'm a car mechanic so I understand the engine, I do (meticulous) Maintenance in the winter so I'm (relatively) trouble free during the season (face it....with any 20 yr. old boat there will be issues sometime).

That being said, if I fished alot, didn't do watersports, didn't enjoy a large swim platform (dates, scuba dive, hang out and swim, and again watersports) or boated in salt water (or shallows) I'd probably own an outboard.

I've owned 4 boats (2 i/o -2 outboards) and the I/O's just "fit" me better.